The present invention relates to semiconductor devices that include copper conductive layers.
Semiconductor devices include metal layers that are insulated from each other by dielectric layers. When copper is used to make those metal layers, it may be desirable to form an etch stop layer or layers, e.g., a layer comprising silicon nitride or silicon carbide, on such copper containing layers. Unfortunately, current processes for applying such an etch stop layer to copper containing layers may yield a device with marginal adhesion between those layers, which may degrade electromigration performance.
Accordingly, there is a need for an improved method for making a semiconductor device that includes copper conductive layers. There is a need for such a process that improves adhesion between copper conductive layers and an etch stop layer that is formed on them. The present invention provides such a process.